package com.uduemc.biso.node.web.utils;

import java.util.Date;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;

public class JwtTokenUtils {
	public static final String TOKEN_HEADER = "Authorization";
	public static final String TOKEN_PREFIX = "Bearer ";

	private static final String SECRET = "jwtsecretbiso";
	private static final String ISS = "echisan";

	// 过期时间是3600秒，既是1个小时
	private static final long EXPIRATION = 3600L;

	// 选择了记住我之后的过期时间为7天
	private static final long EXPIRATION_REMEMBER = 604800L;

	// 创建token
	public static String createToken(String username, boolean isRememberMe) {
		long expiration = isRememberMe ? EXPIRATION_REMEMBER : EXPIRATION;
		return Jwts.builder().signWith(SignatureAlgorithm.HS512, SECRET).setIssuer(ISS).setSubject(username)
				.setIssuedAt(new Date()).setExpiration(new Date(System.currentTimeMillis() + expiration * 1000))
				.compact();
	}

	// 从token中获取用户名
	public static String getUsername(String token) {
		return getTokenBody(token).getSubject();
	}

	// 是否已过期
	public static boolean isExpiration(String token) {
		return getTokenBody(token).getExpiration().before(new Date());
	}

	private static Claims getTokenBody(String token) {
		return Jwts.parser().setSigningKey(SECRET).parseClaimsJws(token).getBody();
	}
}
